The Swedish prosecutor probing the 2022 sabotage of the Nord Stream pipelines linking Russia and Germany said Wednesday he was closing the investigation, citing a lack of jurisdiction.

Prosecutor Mats Ljungqvist said he had had "in-depth cooperation" with German authorities in their investigation, and would "hand over material that can be used as evidence in the German investigation."

The Swedish Prosecution Authority said in a statement the primary purpose of its probe had been to establish whether Swedish citizens were involved and whether Swedish territory had been used to carry out the act.

"Nothing has emerged to indicate that Sweden or Swedish citizens were involved in the attack which took place in international waters," the authority said.

Swedish intelligence agency Sapo also said in a statement that the sabotage was not targeted at Sweden and did not pose a threat to national security.

Ljungqvist said a large number of ship movements had been analysed and that an extensive crime scene investigation had been carried out.

"Against the background of the situation we now have, we can state that Swedish jurisdiction does not apply," Ljungqvist said.

Four large gas leaks were discovered on Nord Stream's two pipelines off the Danish island of Bornholm at the end of September 2022, with seismic institutes recording two underwater explosions just prior to that.

While the leaks were in international waters, two of them were in the Danish exclusive economic zone and two in Sweden's.

The pipelines were not in operation when the leaks occurred, but they still contained gas which spewed up through the water and into the atmosphere.

The pipelines had been at the centre of geopolitical tensions as Russia cut gas supplies to Europe in suspected retaliation to Western sanctions over Moscow's invasion of Ukraine.